“When the digital clock face displayed four zeros on the evening of 31 October this year, the world’s population symbolically reached 7 billion people – an incredible amount considering that only 2.5 billion people lived on earth in 1950.

This growth parallels directly with an increase in the number of people living in cities. In 1950, only 30% of the global population were living in cities, and this figure is predicted to be around 70% by the middle of this century. In a sense, the exact population alive on earth today will be the entire urban population of the world in 2050 – 7 billion people.

The UN’s predictions for South Africa are similar. In 2050 South Africa’s population is expected to be around 60 million people, a 440% increase in population from 1950. 75% of the population will live in cities - 45 million South Africans, 15 million more people in urban environments than today.

From the Greek polis or city state, to Alexandria, London, Prague, Istanbul, Tokyo, Lagos, Sao Paulo and New York all cities have evolved differently, responding to unique social, political, economic and environmental forces – today they stand as idiosyncratic monuments to their histories, struggles and achievements.

A future in which the vast majority of the world’s population will be living in cities begs the question - what will these cities look like and what kind of quality of life will residents have?

What we do know today is that many rapidly growing cities cannot adequately cope with their new populations, most of which settle in informal settlements on the edges of these cities. People are often left to live in the most basic of conditions without any adequate services – they are in a sense peripheral visitors, disconnected from taking part in the city, left in constant impermanence – and today number 33% of global urban citizens.

If cities cannot accommodate the pressures placed on them by current flows of migrants, and given the predicted increase in urban growth, and current levels of unemployment, it seems our urban futures will be more akin to a mega-Mumbai as opposed to a sterile Singapore. No matter your preference - in order to achieve a more sustainable and future proof city, our current urban structures, and ways of living have to be rethought. Johannesburg, Durban, Pretoria and Cape Town are sprawling, suburban cities where residents commute for long hours to and from work everyday, because their places of residence, be they gated communities or informal settlements, are located on the fringes of the city.

This suburban lifestyle, so common to South African cities is possibly the most environmentally and socially unsustainable available to us. Johannesburg produces more waste per person than New York, London, and Shanghai, and more CO2 per person than Mumbai, Sao Paulo and Istanbul combined. While social attitudes to recycling, the environment and low-impact living may be to blame for these statistics, it’s the very way in which our cities have developed – and thus shape our lifestyles that should be questioned.

For example, Johannesburg grew around the motorcar. As its population increased, more vehicles appeared on its roads, roads were widened, and the city grew outwards at low densities. As a divided, apartheid city, the interests of the more mobile white classes were placed above those of the disenfranchised black majority, so very little significant investment was ever made into transportation – and what for? The apartheid government didn’t want to better connect the city at cheap rates – they wanted it as divided as possible, with basic transport available to get the black labour force into the factories and onto the mines.

Today, as a result of this, we experience a city reliant on motor vehicles and widely dispersed communities that are significantly unequal. Where some residents hide behind walls, don’t walk through their streets, don’t know their neighbours and have only experienced a sense of public in shopping malls – others live an entirely public life, in incredibly dense communities where privacy and dignity are often luxuries.

Many cities throughout the world are as socially divided, and face similar problems in future proofing their cities. In Colombia however, two such cities, which were also amongst the most violent on earth, have been completely turned around – and today serve as beacons for the future development of similar cities, including those in South Africa.

Firstly, Bogotá – of drug cartel and soaring murder rate fame, was faced with a large fringe slum population from migration into the city during the last decade. In 1998, Enrique Peñalosa came into power, and radically changed the way the city worked. During his term five mega projects were implemented, which have included a Bus Rapid Transit system known as the Transmilenio, a new system of parks, and an extensive amount of new libraries, road upgrades and cycle lanes. With a serious focus on the architectural and social qualities of the building or space, an engaged public dialogue, and parallel city programmes, this new system of urban improvements reconnected Bogotá.

Following Bogotá’s success, Medellin – Colombia’s second city went through a similar set of changes under the leadership of their mayor Sergio Farjado. His approach was far more fine tuned to the immediate needs of Medellin’s disenfranchised, and through the careful insertion of well considered, top quality schools, libraries and public spaces into troubled parts of Medellin, with the complete buy-in of the public, also together with new city programmes, the rates of violent crime in Medellin dramatically decreased – a sign of better social cohesion.

Be it through Bogotá’s introduction of new systems to tie the city together, or Medellin’s careful, almost acupunctural insertion of the right facilities and public spaces into parts of the city, Colombia was able to turn around its two largest cities, while accommodating a far greater population and preparing for future growth. Allowing them to densify around the right kind of public infrastructure, be they schools, parks, or cycle lanes gave residents access to better facilities, and prevented outward sprawl.

In South Africa, a similar approach can be advocated – given that, like in Bogotá and Colombia, most informal settlement residents have already built their own informal houses. Should they be provided with services, an extensive network of social infrastructure, schools, public space and reliable, safe and cost-effective transport, together with a form of tenure over the land they occupy, it would be expected that investment in individual homes will increase, and a newly mobilized, socially and economically sustainable community will emerge. This process requires a significant move away from the current archaic roll out of individual housing subsidies related to one-house-centred-on-a-plot, on the edge of the city typologies, that differ very slightly from the apartheid roll out.

In looking towards 2012, and the decades that follow, it is vitally important that South African cities are able to critically rethink themselves. The quest to be “World Class” is a delusion, as it glosses over real challenges and real strengths to appeal to global images of what a city should look like. Medellin and Bogotá were motivated by the improvement of the quality of the lives of their residents, and with successful, better informed and mobile residents, both cities are set to grow successfully in the future.

In facing the global growth of urban populations cities need to become more flexible and more accommodating of changes in population. In a sense, cities need to learn from the informal world they often feel so threatened by, and through a resourceful, citizen oriented approach of strategic intervention and service provision, grounded on sustainable public transport, the city of the next few decades should be a better place to live in for more of its residents.”